<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>第6--浮动布局</title>
<style>
    #lside{
        /*width:300px;即没有宽度*/
       width:20px;
       height:100px;
       background:blue;
       float: left;
    }
    #rside {
       background: green;
       height:100px;
       width:20px;
       float:right;
    }
    #common {
        width: 300px;
        hight:500px;
        background: yellow;
    }
</style>
</head>
<body>
    <div id="lside"> 我是左边</div>
    <div id="rside">我是右边</div>
    <div id="common">我是普通div</div>
</body>
</html>